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  Troubleshooting <strong>LLDB</strong>
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                    <h1 class ="postheader">File and line breakpoints are not getting hit</h1>
                    <div class="postcontent">
                        <p>First you must make sure that your source files were compiled with 
                            debug information. Typically this means passing <code>-g</code> to the
                            compiler when compiling your source file.
                        </p>
                        <p>When setting breakpoints in <b>implementation</b> source files
                            (.c, cpp, cxx, .m, .mm, etc), LLDB by default will only search for compile units whose filename matches. If your
                            code does tricky things like using <font color=purple>#include</font> to include source files:
<code><pre><tt>% <b>cat foo.c</b>
<font color=purple>#include</font> "bar.c"
<font color=purple>#include</font> "baz.c"
...
</tt></pre></code>
                        <p> This will cause breakpoints in "bar.c" to be inlined into the compile unit for "foo.c".
                            If your code does this, or if your build system combines multiple files in some way such
                            that breakpoints from one implementation file will be compiled into another implementation file,
                            you will need to tell LLDB to always search for inlined breakpoint locations
                            by adding the following line to your <code>~/.lldbinit</code> file:
                        </p>
<code><pre><tt>% <b>echo "settings set target.inline-breakpoint-strategy always" >> ~/.lldbinit</b></tt></pre></code>
                        <p> This tells LLDB to always look in all compile units and search for breakpoint
                            locations by file and line even if the implementation file doesn't match. Setting breakpoints
                            in header files always searches all compile units because inline functions are commonly defined
                            in header files and often cause multiple breakpoints to have source line information that matches
                            many header file paths.
                        </p>
                        <p> If you set a file and line breakpoint using a full path to the source file, like Xcode does when setting a
                            breakpoint in its GUI on Mac OS X when you click in the gutter of the source view, this path must match 
                            the full paths in the debug information. If the paths mismatch, possibly due to 
                            passing in a resolved source file path that doesn't match an unresolved path in the debug 
                            information, this can cause breakpoints to not be resolved. Try setting breakpoints using the file
                            basename only.
                        <p> If you are using an IDE and you move your project in your file system and build again, sometimes doing a 
                            clean then build will solve the issue.This will fix the issue if some .o files didn't get rebuilt 
                            after the move as the .o files in the build folder might still contain stale debug information with 
                            the old source locations.
                        </p>
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                    <h1 class ="postheader">How do I check if I have debug symbols?</h1>
                    <div class="postcontent">
                        <p> Checking if a module has any compile units (source files) is a good way to check
                            if there is debug information in a module:
<code><pre><tt>
(lldb) <b>file /tmp/a.out</b>
(lldb) <b>image list</b>
[  0] 71E5A649-8FEF-3887-9CED-D3EF8FC2FD6E 0x0000000100000000 /tmp/a.out 
      /tmp/a.out.dSYM/Contents/Resources/DWARF/a.out
[  1] 6900F2BA-DB48-3B78-B668-58FC0CF6BCB8 0x00007fff5fc00000 /usr/lib/dyld 
....
(lldb) <b>script lldb.target.module['/tmp/a.out'].GetNumCompileUnits()</b>
1
(lldb) <b>script lldb.target.module['/usr/lib/dyld'].GetNumCompileUnits()</b>
0
</tt></pre></code>
                        <p> Above we can see that "/tmp/a.out" does have a compile unit, and "/usr/lib/dyld" does not.
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